Computer-animated feature revisits a seemingly long-lost style

Plenty of contemporary animated features are trying so hard to be clever that they forget to be fundamentally enjoyable — and as for the emotional depth, we can appreciate Pixar's impressive track record without dismissing everything that doesn't live up to that standard. 'Rio' manages to be entertaining by working within an unlikely formula: making something that's fun for kids, in the style of movies that their parents would have watched when they were kids. Grade: B.